Oakley, CA Landscaping Rules: Weed Ordinances (2026)

Invasive plant management in Oakley is governed by state noxious-weed law (California Food & Agricultural Code Sections 5004 and 6161), enforced by the Contra Costa County Agricultural Commissioner's Office and supported by the California Invasive Plant Council (Cal-IPC). The State Department of Food and Agriculture rates noxious weeds A (state-eradication target), B (locally prioritized), C (widespread; nursery regulation), and Q (quarantine/unknown). Property owners can be compelled to remove Class A and B species. Common regulated invasives in eastern Contra Costa County include: yellow starthistle (Centaurea solstitialis), medusahead, Italian thistle, purple loosestrife, puncturevine, Arundo donax (giant reed; especially along Marsh Creek and Delta sloughs), pampas grass, Scotch/French broom, Algerian ivy, and periwinkle. Delta-specific aquatic invasives regulated under state and federal law include water hyacinth, water primrose, and Brazilian waterweed, which are managed by the California Division of Boating and Waterways. The sale, transport, and planting of many Cal-IPC High-rated invasives is prohibited or discouraged. Homeowners must not plant these species and should replace existing specimens with natives or non-invasive alternatives. Removal methods include manual pulling (annual weeds before seed set), mowing/cutting (biennials at bolt stage), herbicide application per DPR label, and solarization. Dispose of seed-bearing material in sealed bags with general trash, not green waste (to prevent composting spread). Report suspected Class A noxious weeds to the County Ag Commissioner for identification and response. Nurseries, landscape contractors, and property managers must not install prohibited species.